proposal/mutant/src/bootstrap/org/apache/ant/bootstrap/BootstrapLoader.java - ant - Git at Google

 /*
  * The Apache Software License, Version 1.1
  *
  * Copyright (c) 2001 The Apache Software Foundation.  All rights
  * reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  *
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in
  *    the documentation and/or other materials provided with the
  *    distribution.
  *
  * 3. The end-user documentation included with the redistribution, if
  *    any, must include the following acknowlegement:
  *       "This product includes software developed by the
  *        Apache Software Foundation (http://www.apache.org/)."
  *    Alternately, this acknowlegement may appear in the software itself,
  *    if and wherever such third-party acknowlegements normally appear.
  *
  * 4. The names "The Jakarta Project", "Ant", and "Apache Software
  *    Foundation" must not be used to endorse or promote products derived
  *    from this software without prior written permission. For written
  *    permission, please contact apache@apache.org.
  *
  * 5. Products derived from this software may not be called "Apache"
  *    nor may "Apache" appear in their names without prior written
  *    permission of the Apache Group.
  *
  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  * ====================================================================
  *
  * This software consists of voluntary contributions made by many
  * individuals on behalf of the Apache Software Foundation.  For more
  * information on the Apache Software Foundation, please see
  * <http://www.apache.org/>.
  */

 package org.apache.ant.bootstrap;

 import java.io.*;
 import java.util.*;
 import java.util.zip.*;
 import java.lang.reflect.*;

 /**
  * Bootstrap class to build the rest of ant with a minimum of user intervention
  *
  * The bootstrap class is able to act as a class loader to load new classes/jars
  * into the VM in which it is running.
  *
  * @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
  */
 public class BootstrapLoader extends ClassLoader {
     static public final String RECURSION_GUARD = "ant.bootstrap.recursionGuard";
     static private final int BUFFER_SIZE = 1024;

     private String[] classpathElements;

     public BootstrapLoader(String classpath) {
         StringTokenizer tokenizer = new StringTokenizer(classpath, File.pathSeparator);
         classpathElements = new String[tokenizer.countTokens()];

         for (int i = 0; tokenizer.hasMoreTokens(); ++i) {
             classpathElements[i] = tokenizer.nextToken();
         }
     }

     protected Class findClass(String name)
                    throws ClassNotFoundException {
         String resourceName = name.replace('.', '/') + ".class";
         InputStream classStream = getResourceStream(resourceName);

         if (classStream == null) {
             throw new ClassNotFoundException();
         }

         try {
             return getClassFromStream(classStream, name);
         }
         catch (IOException ioe) {
             ioe.printStackTrace();
             throw new ClassNotFoundException();
         }
     }

     /**
      * Get a stream to read the requested resource name.
      *
      * @param name the name of the resource for which a stream is required.
      *
      * @return a stream to the required resource or null if the resource cannot be
      * found on the loader's classpath.
      */
     private InputStream getResourceStream(String name) {
         // we need to search the components of the path to see if we can find the
         // class we want.
         InputStream stream = null;

         for (int i = 0; i < classpathElements.length && stream == null; ++i) {
             File pathComponent = new File(classpathElements[i]);
             stream = getResourceStream(pathComponent, name);
         }

         return stream;
     }


     /**
      * Get a stream to read the requested resource name.
      *
      * @param name the name of the resource for which a stream is required.
      *
      * @return a stream to the required resource or null if the resource cannot be
      * found on the loader's classpath.
      */
     public InputStream getResourceAsStream(String name) {
         return getResourceStream(name);
     }

     protected Class loadClass(String name,
                               boolean resolve)
                    throws ClassNotFoundException {
         Class requestedClass = findLoadedClass(name);
         try {
             if (requestedClass == null) {
                 requestedClass = findClass(name);
                 if (resolve) {
                     resolveClass(requestedClass);
                 }
             }
             return requestedClass;
         }
         catch (ClassNotFoundException cnfe) {
             return super.loadClass(name, resolve);
         }
     }

     /**
      * Get an inputstream to a given resource in the given file which may
      * either be a directory or a zip file.
      *
      * @param file the file (directory or jar) in which to search for the resource.
      * @param resourceName the name of the resource for which a stream is required.
      *
      * @return a stream to the required resource or null if the resource cannot be
      * found in the given file object
      */
     private InputStream getResourceStream(File file, String resourceName) {
         try {
             if (!file.exists()) {
                 return null;
             }

             if (file.isDirectory()) {
                 File resource = new File(file, resourceName);

                 if (resource.exists()) {
                     return new FileInputStream(resource);
                 }
             }
             else {
                 ZipFile zipFile = null;
                 try {
                     zipFile = new ZipFile(file);

                     ZipEntry entry = zipFile.getEntry(resourceName);
                     if (entry != null) {
                         // we need to read the entry out of the zip file into
                         // a baos and then
                         ByteArrayOutputStream baos = new ByteArrayOutputStream();
                         byte[] buffer = new byte[BUFFER_SIZE];
                         int bytesRead;
                         InputStream stream = zipFile.getInputStream(entry);
                         while ((bytesRead = stream.read(buffer, 0, BUFFER_SIZE)) != -1) {
                             baos.write(buffer, 0, bytesRead);
                         }
                         return new ByteArrayInputStream(baos.toByteArray());
                     }
                 }
                 finally {
                     if (zipFile != null) {
                         zipFile.close();
                     }
                 }
             }
         }
         catch (Exception e) {
             e.printStackTrace();
         }

         return null;
     }

     /**
      * Read a class definition from a stream.
      *
      * @param stream the stream from which the class is to be read.
      * @param classname the class name of the class in the stream.
      *
      * @return the Class object read from the stream.
      *
      * @throws IOException if there is a problem reading the class from the
      * stream.
      */
     private Class getClassFromStream(InputStream stream, String classname)
                 throws IOException {
         ByteArrayOutputStream baos = new ByteArrayOutputStream();
         int bytesRead = -1;
         byte[] buffer = new byte[1024];

         while ((bytesRead = stream.read(buffer, 0, 1024)) != -1) {
             baos.write(buffer, 0, bytesRead);
         }

         byte[] classData = baos.toByteArray();

         return defineClass(classname, classData, 0, classData.length);
     }


     static private void buildAnt() {
         System.out.println("Bootstrapping Ant ...");

     }

     static private void runWithToolsJar(String[] args) {
         try {

             String javaHome = System.getProperty("java.home");
             if (javaHome.endsWith("jre")) {
                 javaHome = javaHome.substring(0, javaHome.length() - 4);
             }
             File toolsjar = new File(javaHome + "/lib/tools.jar");
             if (!toolsjar.exists()) {
                 System.out.println("Unable to locate tools.jar. expected it to be in " +
                                            toolsjar.getPath());
                 return;
             }
             String newclasspath = toolsjar.getPath() + File.pathSeparator +
                                   System.getProperty("java.class.path");

             System.out.println("New Classpath is " + newclasspath);

             BootstrapLoader loader = new BootstrapLoader(newclasspath);

             Class newBootClass = loader.loadClass("org.apache.ant.bootstrap.BootstrapLoader",
                                                   true);
             final Class[] param = { Class.forName("[Ljava.lang.String;") };
             final Method main = newBootClass.getMethod("main", param);
             final Object[] argument = { args };
             main.invoke(null, argument);
         }
         catch (Exception e) {
             e.printStackTrace();
             throw new RuntimeException("Unable to run boot with tools.jar");
         }
     }

     static public void main(String[] args) {
         // check whether the tools.jar is already in the classpath.
         try {
             Class compilerClass = Class.forName("sun.tools.javac.Main");
             System.out.println("Compiler is available");
         } catch (ClassNotFoundException cnfe) {
             if (System.getProperty(RECURSION_GUARD) != null) {
                 cnfe.printStackTrace();
                 System.out.println("Unable to load compiler");
                 return;
             }
             System.setProperty(RECURSION_GUARD, "yes");
             System.out.println("Compiler is not on classpath - locating ...");
             runWithToolsJar(args);
             return;
         }

         buildAnt();
     }
 }
	/*
	* The Apache Software License, Version 1.1
	*
	* Copyright (c) 2001 The Apache Software Foundation. All rights
	* reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	*
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	*
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in
	* the documentation and/or other materials provided with the
	* distribution.
	*
	* 3. The end-user documentation included with the redistribution, if
	* any, must include the following acknowlegement:
	* "This product includes software developed by the
	* Apache Software Foundation (http://www.apache.org/)."
	* Alternately, this acknowlegement may appear in the software itself,
	* if and wherever such third-party acknowlegements normally appear.
	*
	* 4. The names "The Jakarta Project", "Ant", and "Apache Software
	* Foundation" must not be used to endorse or promote products derived
	* from this software without prior written permission. For written
	* permission, please contact apache@apache.org.
	*
	* 5. Products derived from this software may not be called "Apache"
	* nor may "Apache" appear in their names without prior written
	* permission of the Apache Group.
	*
	* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
	* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
	* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
	* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
	* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
	* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	* SUCH DAMAGE.
	* ====================================================================
	*
	* This software consists of voluntary contributions made by many
	* individuals on behalf of the Apache Software Foundation. For more
	* information on the Apache Software Foundation, please see
	* <http://www.apache.org/>.
	*/

	package org.apache.ant.bootstrap;

	import java.io.*;
	import java.util.*;
	import java.util.zip.*;
	import java.lang.reflect.*;

	/**
	* Bootstrap class to build the rest of ant with a minimum of user intervention
	*
	* The bootstrap class is able to act as a class loader to load new classes/jars
	* into the VM in which it is running.
	*
	* @author <a href="mailto:conor@apache.org">Conor MacNeill</a>
	*/
	public class BootstrapLoader extends ClassLoader {
	static public final String RECURSION_GUARD = "ant.bootstrap.recursionGuard";
	static private final int BUFFER_SIZE = 1024;

	private String[] classpathElements;

	public BootstrapLoader(String classpath) {
	StringTokenizer tokenizer = new StringTokenizer(classpath, File.pathSeparator);
	classpathElements = new String[tokenizer.countTokens()];

	for (int i = 0; tokenizer.hasMoreTokens(); ++i) {
	classpathElements[i] = tokenizer.nextToken();
	}
	}

	protected Class findClass(String name)
	throws ClassNotFoundException {
	String resourceName = name.replace('.', '/') + ".class";
	InputStream classStream = getResourceStream(resourceName);

	if (classStream == null) {
	throw new ClassNotFoundException();
	}

	try {
	return getClassFromStream(classStream, name);
	}
	catch (IOException ioe) {
	ioe.printStackTrace();
	throw new ClassNotFoundException();
	}
	}

	/**
	* Get a stream to read the requested resource name.
	*
	* @param name the name of the resource for which a stream is required.
	*
	* @return a stream to the required resource or null if the resource cannot be
	* found on the loader's classpath.
	*/
	private InputStream getResourceStream(String name) {
	// we need to search the components of the path to see if we can find the
	// class we want.
	InputStream stream = null;

	for (int i = 0; i < classpathElements.length && stream == null; ++i) {
	File pathComponent = new File(classpathElements[i]);
	stream = getResourceStream(pathComponent, name);
	}

	return stream;
	}



	/**
	* Get a stream to read the requested resource name.
	*
	* @param name the name of the resource for which a stream is required.
	*
	* @return a stream to the required resource or null if the resource cannot be
	* found on the loader's classpath.
	*/
	public InputStream getResourceAsStream(String name) {
	return getResourceStream(name);
	}

	protected Class loadClass(String name,
	boolean resolve)
	throws ClassNotFoundException {
	Class requestedClass = findLoadedClass(name);
	try {
	if (requestedClass == null) {
	requestedClass = findClass(name);
	if (resolve) {
	resolveClass(requestedClass);
	}
	}
	return requestedClass;
	}
	catch (ClassNotFoundException cnfe) {
	return super.loadClass(name, resolve);
	}
	}

	/**
	* Get an inputstream to a given resource in the given file which may
	* either be a directory or a zip file.
	*
	* @param file the file (directory or jar) in which to search for the resource.
	* @param resourceName the name of the resource for which a stream is required.
	*
	* @return a stream to the required resource or null if the resource cannot be
	* found in the given file object
	*/
	private InputStream getResourceStream(File file, String resourceName) {
	try {
	if (!file.exists()) {
	return null;
	}

	if (file.isDirectory()) {
	File resource = new File(file, resourceName);

	if (resource.exists()) {
	return new FileInputStream(resource);
	}
	}
	else {
	ZipFile zipFile = null;
	try {
	zipFile = new ZipFile(file);

	ZipEntry entry = zipFile.getEntry(resourceName);
	if (entry != null) {
	// we need to read the entry out of the zip file into
	// a baos and then
	ByteArrayOutputStream baos = new ByteArrayOutputStream();
	byte[] buffer = new byte[BUFFER_SIZE];
	int bytesRead;
	InputStream stream = zipFile.getInputStream(entry);
	while ((bytesRead = stream.read(buffer, 0, BUFFER_SIZE)) != -1) {
	baos.write(buffer, 0, bytesRead);
	}
	return new ByteArrayInputStream(baos.toByteArray());
	}
	}
	finally {
	if (zipFile != null) {
	zipFile.close();
	}
	}
	}
	}
	catch (Exception e) {
	e.printStackTrace();
	}

	return null;
	}

	/**
	* Read a class definition from a stream.
	*
	* @param stream the stream from which the class is to be read.
	* @param classname the class name of the class in the stream.
	*
	* @return the Class object read from the stream.
	*
	* @throws IOException if there is a problem reading the class from the
	* stream.
	*/
	private Class getClassFromStream(InputStream stream, String classname)
	throws IOException {
	ByteArrayOutputStream baos = new ByteArrayOutputStream();
	int bytesRead = -1;
	byte[] buffer = new byte[1024];

	while ((bytesRead = stream.read(buffer, 0, 1024)) != -1) {
	baos.write(buffer, 0, bytesRead);
	}

	byte[] classData = baos.toByteArray();

	return defineClass(classname, classData, 0, classData.length);
	}


	static private void buildAnt() {
	System.out.println("Bootstrapping Ant ...");

	}

	static private void runWithToolsJar(String[] args) {
	try {

	String javaHome = System.getProperty("java.home");
	if (javaHome.endsWith("jre")) {
	javaHome = javaHome.substring(0, javaHome.length() - 4);
	}
	File toolsjar = new File(javaHome + "/lib/tools.jar");
	if (!toolsjar.exists()) {
	System.out.println("Unable to locate tools.jar. expected it to be in " +
	toolsjar.getPath());
	return;
	}
	String newclasspath = toolsjar.getPath() + File.pathSeparator +
	System.getProperty("java.class.path");

	System.out.println("New Classpath is " + newclasspath);

	BootstrapLoader loader = new BootstrapLoader(newclasspath);

	Class newBootClass = loader.loadClass("org.apache.ant.bootstrap.BootstrapLoader",
	true);
	final Class[] param = { Class.forName("[Ljava.lang.String;") };
	final Method main = newBootClass.getMethod("main", param);
	final Object[] argument = { args };
	main.invoke(null, argument);
	}
	catch (Exception e) {
	e.printStackTrace();
	throw new RuntimeException("Unable to run boot with tools.jar");
	}
	}

	static public void main(String[] args) {
	// check whether the tools.jar is already in the classpath.
	try {
	Class compilerClass = Class.forName("sun.tools.javac.Main");
	System.out.println("Compiler is available");
	} catch (ClassNotFoundException cnfe) {
	if (System.getProperty(RECURSION_GUARD) != null) {
	cnfe.printStackTrace();
	System.out.println("Unable to load compiler");
	return;
	}
	System.setProperty(RECURSION_GUARD, "yes");
	System.out.println("Compiler is not on classpath - locating ...");
	runWithToolsJar(args);
	return;
	}

	buildAnt();
	}
	}